Chain-gearing.



No. 63,9,0'43. Patented Dec. l2, |889.

T. HEWETT. CHAIN GEABiNG.

Application Bled Feb. 10, 1898..

'No Model.)

ilnirrnn Sternsv irrrcn.

FATENT THOMAS HEWETT, OF LONDON, ENGLAND, ASSIGNOR OF ONE-HALF TO THOMASKERRISON BELLIS, OF SAME PLACE.

CHAIN-GEARING.

SPECIFICATION forming part of Letters Patent No. 639,043, dated December12, 1899.

Application filed February I 1898. Serial No. 669,820. (No model.) l

cation.

This invention has for its object to provide a new and improveddrive-chain designed for driving bicycles and other velocipedes and fora variety of analogous purposes.

To accomplish this object, my invention consists in the features ofconstruction and in the combination of parts hereinafter deg scribed andclaimed, reference being made to the accompanying drawings, in which-Figure 1 is a side elevation of a portion of my improved drive-chain.Fig. 2 is a top plan view of the same. Figs, 3 to 14, inclusive, aredetail views of parts of the chain hereinafter fully described. Fig. 15is a sectional elevation of a portion of my improved drive-chain appliedto a chain-wheel; and Fig. 16 is a detail sectional view taken on' theline a e, Fig. 15.

In order to enable those skilled in the art to make and use myinvention, I will now describe the same in detail, referring to theldrawings, wherein-- The letter e indicates the chain wheel, which isprovided with shoulders l) and radial extensions c to form an annularchannel cl, in which the drive-chain lies. The radial iianges c carryantifriction-rolls e on rivets e. Below the rolls c are formed clearspaces d', which Serve as mud-escape ports in the channelbed d.

I prefer to arrange the rollers e on the inside of the wheel-flanges cin pairs, each pair on one side opposite apair on the other side, and Iarrange the chain to cooperate with the wheel, (either to drive thewheel or to be driven thereby, as the case may be,) with a series ofcentral links f at intervals so arranged that they shall inpoperationwhen in the trough of the wheel lie between the flange-rollers e, withthe ends of two pairs of other linksf lying on either side of theirends,

a rivet f2 securing each three links together at their ends and formingtheir hinge.

The end rivet-holes of the side links f I prefer to form on their outersides countersunk, (see Figs. 3 and 4,) and the pins f2, which connectthem and the central. links f, I form of a larger diameter within eachinner link, with correspondingly-enlarged holes in said inner links, thesmaller outer portions to lie within correspondingly smaller holes intheside-link ends. The projecting ends of this smaller diameter I rivet-'up tightly into the countersunk recesses and grind off any projectionsnot desired, or the said pins need not be riveted, as theantifriction-wheels serve to keep the two side links flush. By thesemeans I am enabled to avoid difficulties of construction and workingthat have been found to arise with chains where the rollers on thechains are mounted on the same axial pins that connectthe several setsof links and also to greatly improve and facilitate the construction ofsuch chains. As a means of connecting the ends of such a chain for usein chain-gearing must be provided, I have designed the device indicatedby Figs. 10, 11, 12, 13, and 14, whereby the parts of thechain-fastening are made so as to lie flush with the sides of the chainand with the an-.

nular channel of the wheel they run in. In order thus to connecttogether the ends or parts ofa length of chain, so' as to form anendless chain, the locking-stud, roller, or pin h to fasten togetheradjacent links of a gearchain is passed through the said links of theends of the chain to be joined and is then locked into position by meansof a leaf, plate, or spring-piece 1l, which is centered on the side faceof the outer link.

The links or plates of the chain to be oonnected are correctly placedrelatively. The short stud 7i, which may have the end first inserted ofa smaller diameter, (see Fig. 10,) leaving therebya smaller hole to beprovided in the link it engages, and a small shoulder h' to determinethe extent of its insertion, is pushed into position, and the springI orplate Y t' is turned over the entrant hole, locking the bolt h therein.A slight projection t" on the inner face of the spring-plate may besprung ICO into a small depression h2 on the outer end of the lock-stud,thereby serving to restrain any disengaging movement of the springplate,or the arrangement can be transposed. The springs are centered on theantifrictionwheel axes,which pass through the link-plates of the chain.These plates i, that box in the locking-studs, are made of spring-steelof the same shape as the chain-links, against which they lie flush,there being no outstanding parts to catch in rollers of the chain-wheel.

The chain described carries antifriction rollers or wheels g, mounted onthe pairs of links f', independent of the studs f2, which serve toconnect the two links of each pair. To accomplish this, I provide pinsf3 f4, (best seen in Fig. 7,) which are loosely inserted throughsuitable holes in the links f and carry the antifriction rollers orwheels on their ends. The part f3 of smaller diameter of each pin ispassed through one of the rollers or Wheels and upset to retain thewhole in proper position. These antifriction rollers or Wheels areadapted as the chain and chain-wheel travel to engage the rollers e.

In a chain-gearing chain constructed as I have described, with axes ofthe antifriction wheels or rollers borne in bearings formed in the linksindependently of the studs connectingthe links, it is foundin practicethatan advantage arises from this construction in that, except at themoment when such chain-roller teeth are actually pulling or are beingpulled by the teeth of a wheel, there is no strain on theiraxes,tvhereas in gear-chains of other constructions there is nearly aconstant strain on the rollers, owing to their having to serve as'connections for the links of the chain.

Having now particularly described and ascertained the nature of my saidinvention and in what manner the same is to be performed, I declare thatwhat I claim is l. A chain consisting of side links arranged in pairs,central links pivoted at their opposite ends between the ends of theside links, transverse pins j ournaled in openings formed in the sidelinks midway between the ends of the latter and in alinement4 with thepivots of the side links, and antifriction-rollers fixed on the-outeropposite ends ot' said pins, substantially as described.

2. In a chain consisting of side links arranged in pairs and centrallinks pivoted at their opposite ends between the ends of the side links,the ends of the side links at the end of the chain being respectivelyprovided with perforations of unequal size, of a joining-pin reduced atone end to fit into the smaller of said perforations and recessed at itsopposite end, and a spring-plate pivoted centrally to one of said sidelinks at th'e end of the chain and provided with aprojection on itsinner face arranged to engage the recessed end of the joining-pin,substantially as described and for the purpose specified.

In testimony whereof I have hereunto set my hand in presence of twosubscribing wit- TIGSSGS.

THOMAS HEWETT. Vtitnesses:

ALFRED GEORGE BRooKEs, ERNEST JOHN HILL.

